<template>
  <div>
    <!-- 上传文件组件 -->
    <el-upload
      ref="upload"
      :action="getActionUrl"
      list-type="picture-card"
      :multiple="multiple"
      :limit="limit"
      :headers="myHeaders"
      :file-list="fileList"
      :on-exceed="handleExceed"
      :on-preview="handleUploadPreview"
      :on-remove="handleRemove"
      :on-success="handleUploadSuccess"
      :on-error="handleUploadErr"
      :before-upload="handleBeforeUpload"
    >
      <i class="el-icon-plus"></i>
      <div slot="tip" class="el-upload__tip" style="color: #838fa1">
        {{ tip }}
      </div>
    </el-upload>
    <el-dialog :visible.sync="dialogVisible" size="tiny" append-to-body>
      <img width="100%" :src="dialogImageUrl" alt />
    </el-dialog>
  </div>
</template>
<script>
import storage from '@/utils/storage'
import base from '@/utils/base'
export default {
  data() {
    return {
      // 查看大图
      dialogVisible: false,
      // 查看大图
      dialogImageUrl: '',
      // 组件渲染图片的数组字段，有特殊格式要求
      fileList: [],
      fileUrlList: [],
      myHeaders: {},
    }
  },
  props: ['tip', 'action', 'limit', 'multiple', 'fileUrls'],
  mounted() {
    this.init()
    this.myHeaders = {
      Token: storage.get('Token'),
    }
  },
  watch: {
    fileUrls: function (val, oldVal) {
      //   console.log("new: %s, old: %s", val, oldVal);
      this.init()
    },
  },
  computed: {
    // 计算属性的 getter
    getActionUrl: function () {
      // return base.url + this.action + "?token=" + storage.get("token");
      return `/${this.$base.name}/` + this.action
    },
  },
  methods: {
    // 初始化
    init() {
      //   console.log(this.fileUrls);
      if (this.fileUrls) {
        this.fileUrlList = this.fileUrls.split(',')
        let fileArray = []
        this.fileUrlList.forEach(function (item, index) {
          var url = item
          var name = index
          var file = {
            name: name,
            url: url,
          }
          fileArray.push(file)
        })
        this.setFileList(fileArray)
      }
    },
    handleBeforeUpload(file) {},
    // 上传文件成功后执行
    handleUploadSuccess(res, file, fileList) {
      if (res && res.code === 0) {
        fileList[fileList.length - 1]['url'] = 'upload/' + file.response.file
        this.setFileList(fileList)
        this.$emit('change', this.fileUrlList.join(','))
      } else {
        this.$message.error(res.msg)
      }
    },
    // 图片上传失败
    handleUploadErr(err, file, fileList) {
      this.$message.error('文件上传失败')
    },
    // 移除图片
    handleRemove(file, fileList) {
      this.setFileList(fileList)
      this.$emit('change', this.fileUrlList.join(','))
    },
    // 查看大图
    handleUploadPreview(file) {
      this.dialogImageUrl = file.url
      this.dialogVisible = true
    },
    // 限制图片数量
    handleExceed(files, fileList) {
      this.$message.warning(`最多上传${this.limit}张图片`)
    },
    // 重新对fileList进行赋值
    setFileList(fileList) {
      var fileArray = []
      var fileUrlArray = []
      // 有些图片不是公开的，所以需要携带token信息做权限校验
      var token = storage.get('token')
      let _this = this
      fileList.forEach(function (item, index) {
        var url = item.url.split('?')[0]
        if (!url.startsWith('http')) {
          url = _this.$base.url + url
        }
        var name = item.name
        var file = {
          name: name,
          url: url + '?token=' + token,
        }
        fileArray.push(file)
        fileUrlArray.push(url)
      })
      this.fileList = fileArray
      this.fileUrlList = fileUrlArray
    },
  },
}
</script>
<style lang="scss" scoped></style>
